| Level I | Good quality evidence |
Systematic review of RCTs with consistent findings High quality individual RCT |
| Level II |
Limited quality patient orientated evidence |
Systematic review of lower quality studies or studies with inconsistent findings Low quality clinical trial Cohort studies Case-control studies |
| Level III | Other |
Consensus guidelines, extrapolations from bench research, usual practice, opinion, disease-oriented evidence (intermediate or physiologic outcomes only), or case series |
[9] Organic nitrates (Isosorbide mononitrate and dinitrate, oral): Thadani U, Lipicky RJ. Short and long-acting oral nitrates for stable angina pectoris.Cardiovasc Drugs Ther. 1994 Aug;8(4):611-23. https://www.ncbi.nlm.nih.gov/pubmed/7848896
Organic nitrates (Isosorbide mononitrate and dinitrate, oral): Parker JO. Eccentric dosing with isosorbide-5-mononitrate in angina pectoris.Am J Cardiol. 1993 Oct 15;72(12):871-6. https://www.ncbi.nlm.nih.gov/pubmed/8213541